Ignition system



March 21, 1950 M. A. RUDD IGNITION SYSTEM Filed Aug. 29, 1945 INVENTOR. Wm J4 M Y 09% A fiaam/ ATTORNEY.

Patented Mar. 21, 1950 IGNITION SYSTEM" M'aumicef A'...Rudd,=; North Plainfiel'd; N: J assig'nom to. Bendix Aviation Corporations. New Yorke. N. Y a corporationof Delaware Appiicationnugust 29, 1945; Serial No; 613316":

20 Claim-s1;

This: invention. relatesato electrical apparatus and more particularly to: an electrical control system adapted for use: in controlling the: ig= nition system for: one" or"-.'a-:1-plurality oti' aircraft engines.

Oneof the objects:ofithe-presentiinventiorr isito provide: a -control circuit and means. for effecting control. of the: ignition circu-it or :anengine or the like. from: aremote'fposition.

Another'object iisl to" provi'deoaacontroll system of the abovelleharacter whichlproyidesf safety; particularly inmombat aircraiti Still another object othe inyention is to pro vide a simpl'e yeti effectiim means foricontrollin g. a larger-number"oteircuits sueh'as ignition sci'rouits from; a. remotesposition and 1.: ina certain: selected combinations.

Another object isto provid'e noveiIremote control. means former or a plurality of electrical circuits" whereby the: number, length and weight of electrical leads is "minimized and the space re quirements are out;

Another object is. to provide an electrical control system for the ignition -cir'euit" of an interrial combustion engine 'or "other electrical' instru mentality which ise n'ot required tobe shielded to peven-t" interferenceiwithrad-1'0 receiving ap paratus;

Another object is to coordinate a master circuit' sucir as thatdiseiosedE in'this application with particular instruments" adapted for use therein such-asare disc'losed' in co-pendirrg applications Serial Nos. 613,317 and: 613*,318; filed August 29;, 1945! The above and further. objects and novel tea.- tures of the inventionwiii morefully; appear from the follbwingdetailed description when the same is read in connection" with the." accompanying drawings. ever, that the drawing-is for the purpose o-fillus tration only, and is not'iritenddto definethe limits of the. invention, reference .for this latter purpose being, had'primarily to. the appended claims.

The single figure .ofLthe .drawingiisl a. diagrammatical representationroiiial master. circuit.- at the type-described, operable; from atremote distance through-a. small. number. of; l wires .by master or.

control switches.- indioatedtgenerallyby numerals ofawhiohshas teem-shown; it beingrunderstood It is to be expresslylunderstood, how- 2;; that each of: tl'i'ei' other leads is" similarly connectedi The-apparatus described iii-application Serial No! 613 ,3' 18 is adapted lfor" use irr-pl ace of switch NJ andrthe apparatus described in application Serial No.- 613317 'is adapted for use inplrace of switch it; i't be" g understood that those inventions are not limited to"us'e =with this inventionalthough-they contribute-to its success.

controlw system illustrated diagrammatioally' andi hy wayofi-*'examp1e in the accompanyin g 'rdrawings isvon "adapted 'for'usel in" .controlling the operationuoif the i'ignition circuits of all four engines: of a four-engine aircraft, each. ofis equipped" with seven "dual type magnetos having: two coils: operating: through separate cir cums-to supply eurrent thfl'flfigh separate distributors to one-bani: "ot spark plugsof one row of a multi-row engmei Im systems of thistype the right-hand E coil in' a magneto serves the: righth'andibankxof-spark plugs in one cylinder row and the lett-hand icoil serves the other "bank of Spark plugs imthe same row of cylinders. In airc'rait havingrour engines, the engines are necessarily mounted: at aisubstantial distance" from the pilots cabirrxann from the flight engineers control. paneliso that the usual controlmeans for the ignition systems thereof requires th'e use of a large 'numb'er oi long conductors; the very weightioriwhiehisobjectionable and the length orwhich increases their vulnerability and the vuinerability of the airplane? Furthermore, all such leadsareprospective sources of radio leakage and interference and" frequently require radio shielding:whichaddsaobjectionahl eweight to what is-alr'eady too heavy? Forthepurposeiot ilrustratiom one side oi? one magnem and! a complte control system for one engine are sho'Wnr The systems-for all engines are identical with that illustrated? Each mag; n-etolihasarlefteofl: consisting of a primary wind: ingr l Errand: arseeonldary.winding l 6:; the former of. which is connected.inreircuitrwith a" cam op-j erated: circuit' 'breaker l'i :and a condenserw s the usual. manner; Ihe-sec'ondary windin g "5 is connected through: as distributor I9 with a pin ralityot sparloplugsszfl; the number' of which corresponds to the numberiotfcyiinders hr the cyl'iirden row. l It?wilt.bekunderstoodibyvmeehanies that the system: is :as-: applicablertnengineslhaving -onlly one cylinder per: row" as: to? those having a pin rality thereof. Each magneto containseoiisand cireuits 'imzwhictr electrical energy is: generated in: aiknowm mannerib "aisi'z agl'e -magneto rotor-or equivalent meansi wh iohi are not shown One end of the primary winding I is permanently grounded at 2| and provision is made through a switch 23 whereby the other end of said primary coil may be grounded. It will be readily understood by persons skilled in the art that when both ends of the primary coil are grounded the magneto coil is inoperative and no energy is furnished at the spark plug. In the usual system this is accomplished by manually closing an ignition switch. In the present installation, the purposes of the invention are accomplished by novel circuits and remote control wherein the lefthand bank of spark plugs may be affected in coordination with the right-hand bank so that one or the other bank may be separately tested.

A novel relay or operating switch so-called to distinguish it from the novel master or control switch ID, has stationary contacts 22 each of which is connected by a lead I2 to one of the primary coils 5 of one of the seven magnetos of an engine. Movable element 23 of the ignition switch is illustrated as being semi-circular and having contact brushes 24 on the curved perimeter thereof that are adapted for simultaneous engagement with contacts 22. The brushes 24 may be connected to ground as at 25 in any suitable manner such as through armature member 26 and the pivotal mounting thereof. The said member 23 is provided with a suitable armature 2B in operative relation to a plurality of electromagnets 27 and 28. The contacts 22 and 24 are closed by magnet 21 by throwing the armature and the member 23 in a clockwise direction about a pintle 29. The electromagnet 28 moves the brushes 24 out of engagement with the contacts 22 by throwing the armature 26 in the reverse direction. The armature 26 may be yieldably held in each of its two extreme positions by any suitable means such as a cam faced pivoted latch 30 which is held in engagement with the armature by means of a spring 3|, and the cams of which are engageable with opposite sides of the armature and hold the member in a selected position. The effect of spring 3| and the cams on lever 30 is less than the effect of the magnet 21 or 28 so that the energizing of the proper magnet will always throw the switch and will not be prevented by the lever.

Novel simplified means which insure maximum safety are provided for energizing the coils of the electromagnets 21, 28 to effect the desired operation of switch member 23. As shown, one end of coil 21 is connected through a lead a to ground at 4|] and one end of coil 28 is connected by a lead 27 to the ungrounded terminal of a source of electrical energy such as a battery 4| through a bus line 0 which may extend through both wings and the fuselage of the aircraft. The other terminals of coils 21 and 2B are connected to resilient or movable switch arms 42 and 43, respectively, which are adapted to alternately contact a central contact arm 44. The alternate connection is effected by an actuating arm connected to armature 26. When the latter is in the illustrated position, the arm engages spring 42 holding it out of contact with central arm 44 and permitting spring arm 43 to make contact therewith. When armature 26 is moved to its other position, spring 42 is permitted to contact arm 44 and spring 43 is moved out of contact therewith. Both arms 42 and 43 are normally biased toward engagement with arm 44.

Switch arm 44 is connected by a control wire it to a terminal of the control switch Ill, which is usually located on the flight engineers control panel. Terminal 50 is adapted to be connected with any one of four contacts or switch points 0, R, L or B through a pivoted lever 5|. During normal operating conditions, contacts B and L are connected to ground through lead 6, an emergency switch 60, a lead ,1 and a second emergency switch 6|. Any number of such emergency switches may be provided for simultaneously making all engines inoperative. Contacts R and O are connected to bus line 0 through lead g and thence to the source 4| of electrical energy.

The emergency switch 6| is a simple, two-position switch; when it is in on position it connects terminals of the control switch In to ground and when it is in off position it connects the same terminals to the source of energy 4| through lead g and bus line 0.

In the novel system that is thus described, there is provided engine ignition control wherein the application of ground to a relay switch causes it to turn the engine on, and application of battery to the relay switch causes it to turn the engine off. This statement, although true, is deceptive in its simplicity because the conceptions that were required to attain this simplicity, and the mechanism that accomplishes it, are complex.

As shown in the drawing, the switch BI is in the on position, the switch 66 is in the on position, the switch 5|is connected to switch point R, switch contacts 43 and 44 are engaged and switch elements 24 are engaged with switch elements 22. Under these circumstances, the battery is connected through lead b to coil 28, contacts 43 and 44, lead d, switch arm 5|, point R and lead g to the bus line c at 0. Therefore, both sides of coil 28 are connected to power and the coil is not energized. Inasmuch as the switch points 44 and 42 which control coil 2'! are held open by arm 45 attached to armature 26, coil 21 is also not energized. If the engineer moves the switch arm 5| to point L, current will flow from batery 4| through lead b to coil 28, through switch arms 43, 44, switch 5| and point L to line e Where it passes through switches 66 and BI to ground, completing the circuit and energizing. coil 28 which attracts the armature and throws the switch brushes 24 out of engagement with contacts 22. As soon as the relay switch has operated, the buifer on the end of arm 45engages the contact 43 and moves it out of engagement with contact 44, breaking the circuit and de-energizing the coil 28. In this new position the coil 2'! is connected through the lead a to ground at 4!) and through lead h to arm 42 which is now in engagement with contact 44, lead (1, contact 5|, point L, lead e, switch 60, lead 1, and switch 6| to ground. Both sides of coil 21 are consequently connected to ground and that coil is also not energized. By this means current is turned oif in each instance as soon as the relay has operated, so that energy is used only during activation of a coil.

The bus line 0 and lead 9 constitute a power line; the line 6, f constitutes a ground line. It will be observed that the points 0 and R. of switch H) are connected to the power line and the points L and B are connected to the ground line. Thus, the contact 44 will be connected to ground whenever the switch 5| is in engagement with either point L or B and with power whenever the switch 5| is connected with points R and 0. Since the contact 44 is always in engagement with coil 21 or coil 28 through the contacts 42 or 43, respectively, the coil thus contacted will also be connected to ground or power as the case may be.

aromatics 6?; Therefore;- it istheconnectiomot-coitmrtozgrmmi emimessat once he putts theeswitelzrwiu whichnal whichmakes thee engine'soperative andt tlre lows-the centerspringfli,.whichrissbiaseditoward: nection': of": coil 21;; to". powerr which makes; 117.1 content-13; tom-break irornrcontact "sand: engage. inoperative; the contact 13. When this is done; alrrel'ay It isfrequently'desirable-tarot ,OIIfliZOflB banker? switches, thromtheiracontacts into. engagement plugs: in order-that'tests mayub'einmzorrthezother? witn tnercoil-vconneoted contactsssouthataall coils bank. In. orderto accomplislrthis; atseparaitaoire ameaimmediately': grounded and; the engines: stop cuit'substantiallyidenticarvwithrthatriwhioh has for-locket spark; Similarly thepil ot' wishes. been described; is: provided ion the rightehandi tosstooalllither engines: heemayn throwvv the. switch banksof plugs. The systemwhichwhasslfistbeen: 1o; Shinto.- thelfo f positiomproducing aasimilar re described :is. lettered: L: and ishowsrseveirleadsiz [it suits; going tov the seven coils: ithatrserve nthelleftehand 1 ill-scam be? emitted by: connecting leads:

banks of plugs. Similarly; sevenwleadszvflagootoa erwctvf; andriswitchnfifli canbe omittedbycon the coils that serve the rightehandibanks ot' pitrgsv nectingcontactllito ground;v and are similarlm'controlled byia. relayvswitclr 63 15, Arr advantage of th'e inventiom is in saving-the" which is connected througlracswitchjllifi, 43R ofiilong 'leacls; Another advantageof-ithe 44R and lead d! to switch: which;alsoshassiourts invention is therelative simplicity of the panel contact points 0,112.11 LandB iwhichmdifiervfroml moon-ted apparatus. Another" advantage 1 contact points and B offswitchMiinothat; makinggth er-r'ightianctilefibbanks 01 plugs in each point-R'is connectedtoi the ground-line and'iL. engine separately"available fontesting; Another to the batteryline. The'switch'arms ilrand 65 advantage is imeach -oftire means andmethod-sareconnected by a rack; 53. which: is operated by that: have beerr invented toaccomplish themaniazrpinion 52'as shown so thatfthetwo'cirouitsrmay fold and complex conceptions-involved in this inbe controlled simultaneously; Whenboth switch vention. A -furthenadvantage isirr the coord inaarms and 65 strain: engagementl withpoints-O tion of the parts-0ttwoormorecomplexelectrical both relay switches;are:thrownyso.thatithesswitch. systems and the reductionot'the complexity of points are in engagement: andall the coils are control-:tothe simple o-peratioirof a dial or a grounded. -When.,the SW1tCI'-l arms 5 65 are-in'. handle:

the position R;.;the left coils'are grounded'and theo It will be perceived by engineers that the inright coils arein operation, as shown in the draw- 3o vemiflnhhias monyiuses and that h p ficings. When switch-arms. 5|, sfi are inengages-s while comprehending great novelty-i r ritself is ment with: points L the lert-handfcoirs are operonly illustrative The: system-composed of switch ating and the right-hand coils; are grounded; l fl' and switeh H iis'adaptable to the remotecom When arms 5|, 65 COntaGtlpO1nt$fiB bOthl SetS of trol.of manminstrumentalitiesand the system coils operate. comprisedofi'switches I 0 amt-Gland the relay It will be observedthatr one side of each magnet switches I l and ifi tc: Which they are connected" coil 121, 21B. is connected to ground; and smoother is -adaptable to the coordination of other elecother' side is connectibler through the relay r c s rumentafitiesr switches and switches: l0, fill eitherto ground orr wl'llile'flnlo"'meembodimem e p se irre to'poweri When that connectio listt' t m nd; 401 vention has been illustrated and described in do the circuit will extend from ground-to ground "audit tail, it -iS1"t0-' bee p ess y" ood a t e no current will flow-to energize th t same is notrl tmited to said embodiment. Various b t. t at h t connection,cat switchesc mu changes may be.made' irr-the-materials suggested" 64 is to a power so r t il flowmfrom: andin the design andarrangemerit ofthe parts power source to ground and thgmagnet; ir uit illustrate di witliout cleparti' ng from the spirit and will. be energized. scopeof rthe invention, as will now be clear-to Similarly, 1 1 each, magnet 1-3;; gag-F thoseskfllediin the art. For a definition" of the per anentl onn t d. c somceyof power Such, limitsv of therinvention; reference is had' primarily as battery 4| and thQTOthBIItSidviSgECODHECflblG mth'e appended? through; the. switches: to: power source-- or towhafii'is claimedig? ground. When-ithecormection:issto' owensourcea 1'. Control means for an ignition system or thecircuit will extendfrompowersourcetopower the like= compr s g" a" plu y-- ofcoordinated" source and. nopcurrent-"will i'lovwito energizethe switches adapfi d fio e n ed and j ou ded magnet, but; when connection is to groundz tlow pp yor together, a plura y of movable magnet :will be energized; meansadapted b'wmotion to control a plurality A substantial'advantage .ofthe-foregdng cone. of instrumentalities, apl'uralitwofmeans conoeptionis thatnpower iSi'USBdJ only.momentarily nflctfidi 0 ll y ofiswitflhes'and adapted and is immediatelyturnedwofias soon as th'e setomovesaid ereby themovelected magnet h ti d merit.ithereof may be controlled andcoordinated Ifdesired; azsource of Ipower may be madetoy fl Coordinatediswitchefir u l booster current thmgughrfijnes 11:; asmoreu 2;:Contro1;-means@ for: an ignition system i or" fully described in one said:co-pendingwppllcathe-dime N- g"a'-D u --w da lm tion'. Three other pairs. oftcoordlnated switchess cfmnecflfon; p ir of -sw-itches -hav II, III, IV may be madertoizcontrolisimil ar on meamvadapted fioconnectasaid s--toeether-- cuits for three. other engines;and theirconnecpp ely o p a -g d; a d a pa r tions to the groundrand: bus linesz-arer-mdicated of re ati sw e fi a D d =c n w h sothat the inwentiommayvbe readily appliediebw' saild swifiches aridtowpower-and er unddn' ac persons Skilled v thorax; m .fouxxengjngdriplangs V cor-dance with the -=setting of "the said: switches;

In this system, the relay switcheszare located 32 A'meane'of' controlfor an ignition systemm close proximity to; they;engineqsothatrtherfour- 01* the like comprising?- a power source and a teen lead lines are, short;camberwelklprotected: ground, connection; a pairof-switches having" without.adding;,obdoctionablewweightandsioflierva: pointssimilarly connected to" power and' to minimum orlength;zexDosedmo-lenemwactiom or: ground andpoi'ntsoppositelyw connected to :power accidentalinjuryrand ground and having. a. pair ofcoordinated lithefheht engineer W-ishesrto ltuem oiftallttheza?! contaobs=addptecfito=-eneagesaid pofnts and to be connected respectively with a pair of relayswitches, whereby said relay'switches may be simultaneously or oppositely connected to power and ground.

4. In apparatus of the type described a set of magneto coils adapted to be rendered'inoperative by connection to ground, a second set of magneto coils adapted to be simultaneously electrically affected, switch means to aiiect said first set comprising a relay, switch means to affect said second set comprising a relay, a source of power, a ground connection, means to control the switch operating'means of the relays comprising" a' pair of switches having a plurality of points connected with ground, a plurality of points connected with power and'contacts connected with said relays adapted to be selectively engaged with said points, and means to coordinate said contacts with said points whereby to simultaneously or alternately energize the relays and through said switch means to afiect said coils.

5. An ignition system for an engine comprising a pluralit of transformer coils adapted to supply a plurality of spark plugs, a relay switch adapted in one position to render said coils ineffective and thereby. turn the engine off and in another to render the coils effective and thereby turn the engine on, means to apply ground to the switch whereby to turn the engine on, and means to apply battery to the switch whereby to turn the engine oh".

6. An ignition system comprising a plurality of electrical instrumentalities adapted to' be made operative or inoperative simultaneously, control switch means adapted to be connected with a power supply or with ground, and-means made operative by the said connection'to power. to make said instrumentalities inoperative and by said connection to ground to make them operative.

'1. In apparatus'of the type described a set of magneto coils adapted to be made inoperative by connection to ground, another set of magneto coils adapted to be made inoperative by connection to ground, a relay switch adapted in one position to connect one said set toground, a relay switch adapted in one position to connect another said set to ground, a power line and a ground line, means to coordinate the operation of said relay switches whereby to ground said coils alternately or together comprising switch points connected with the power line, switch points connected with the ground line, and switch contacts connected with the relays and adapted to be simultaneously or alternately connected with said power and ground connected points.

8. In apparatus of the type described a set of magneto coilsadapted to be made inoperative by connection to ground, another set of magneto coils adapted to be made'inoperative by connection to ground, a relay switch adapted in one position to connect one said set to ground, a relay switch adapted in one position to connect another said set to ground, a power line and a ground line, means to coordinate the operation of said relay switches whereby to ground said coils alternately or together comprising switch points connected with the power line, switch points connected with the ground line, switch contacts connected with the relays and adapted to be simultaneously or alternately connected with said power and ground connected points, and means to simultaneously throw all relay switches to grounding position. 1

9. Remote control switch means comprising a plurality ofele'ctromagnets, an armature adapted; to be thrown by said magnets, switch means adapted to be operated by said armature, and means to energize said magnets alternately comprising a switch, means to connect the switch to a source of energyor to ground and means to connect the switch to a selected magnet.

10. Remote control means comprising a plurality of electromagnets, an armature adapted to be thrown thereby, and means to selectivel'y'energize said magnets comprising a relay switchand a remote control switch connected'therewith and adapted to selectively connect said relay magnets to power and .toground. 1

11. Remote control means comprising a plural ityof electromagnets, an armature adapted to be thrown thereby, one side of each electromagnet .beingconnected with a switch, the'other side of one electromagnet being connected to ground, r and the other side of the other electromagnet being connected to power, switch means adapted with said switch to complete a circuit through a said magnet, and means to deactivate the said magnet after it has been energized.

2.,Remote control means comprising a plurality of electromagnets, an armature adapted to be thrown thereby, means connecting one side of each said magnet with a switch, means connecting the other side of one said magnet with power, means connecting the other side of the other said magnet with ground, and switch means adapted with said switch to complete a circuit through a means to connect said magnets through said switches in selected combinations to power and to ground.

'14. Remote control means comprising a source of electrical energy, one terminal of which is connected to a power line and the other terminal of which is connected to ground, a relay mechanism comprising an armature, a pair of electro-magnets adapted to be alternately energized by said source for actuating said armature, one terminal of one said magnet being connected to said power line and one terminal of the other said magnet being'connected to ground, and a relay switch means controlled by said armature and comprising a separate contact electrically connected to the other terminal of each of said magnets and a common terminal alternately engageable by said separate contactsto alternately close a corn nection to one of said magnets while breaking a connection to the other magnet, and a control switch means for selectively connecting said common terminal of the relay switch means to the power line or to ground.

-15;v Remote control means as defined in claim 14 including switch means operable by said armature for alternately opening and closing at least one electrical circuit containing an electrical instrumentality.

16. Remote control means as defined in claim 14 comprising other switch means for selectively connecting atleast one terminal of said control switch means to groundor to the power line.

1'7. Remote control means as defined in claim '14 comprisinga plurality of relay mechanisms and a control switch means for each oi said mechanisms.

18. Remote control means as defined in claim 17 comprising other switch means for selectively connecting at least one terminal of each of said control switch means simultaneously to ground or to the power line.

19. Remote control means as defined in claim 14 comprising at least two of said relay mechanisms and wherein said control switch means comprises at least two coordinated switches for selectively connecting the common terminals of the relay switch means simultaneously to ground, simultaneously to the power line, or either one to ground and the other to the power line.

20. Remote control means as defined in claim 19 comprising other switch means for simultaneously connecting selected terminals of both said 10 coordinated switches either to ground or to the power line.

MAURICE A. RUDD.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,275,047 Krantz Aug. 6, 1918 1,861,417 Klaiber May 31, 1932 1,995,780 Phillips Mar. 26, 1935 1,996,268 Ambuhl et al Apr. 2, 1935 2,015,163 Steiner Sept. 24, 1935 2,315,191 Elliott Mar. 30, 1943 

